Deep-seated candidosis has become an important clinical problem in the past two decades because of its frequency in transplant patients, in patients with severe burns, and in those undergoing treatment with corticosteroids or cytotoxic drugs. This research project will develop methods for detecting products of Candida in sera from patients with candidosis. Methods will be refined for measuring levels of antibodies (Ab) to antigens of this organism in sera from infected patients. The applicant has developed radioimmunoassays (RIA) to quantitate levels of serum Ab against cell wall mannan (CWM) or C. albicans and levels of Ab against a major cytoplasmic antigen of Candida. Enzyme-linked immunoabsorbent assays (ELISA) will be developed to make measurement of anti-CWM and anticytoplasmic antigen Ab levels more readily applicable clinically. RIA or ELISA, which can reliably detect small concentrations of the major cytoplasmic antigen of Candida in serum will be developed. The investigator has devised methods to detect CWM in serum but better methods must be developed so that smaller amounts of CWM can be detected in sera which contain anti-CWM Ab. Seqential serum samples will be obtained from patients with acute myelogenous leukemia and from patients in an intensive care unit. The assays described above will be performed on these sera and their usefulness compared in the diagnosis of severe candidosis. In patients who develop severe candidosis, insight into the natural history of the development of these mycoses and approaches to monitoring the treatment of such infections will be obtained.